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THE NEW  STUDENTS  REFERENCE  WORK                                  2159

DECIMAL FRACTIONS.

Decimal fractions, usually called decimals, express one or more of the decimal divisions of a unit. Decimal fractions are generally expressed by writing the numerator only, the denominator being shown by the position of the decimal point, as illustrated by the following: .4               four tenths.

.04             four hundredths.

.004           four thousandths.

.0004         four ten-thousandths.

.00004        four hundred-thousandths. ,000004      four millionths.

Eead the decimal as if it were a whole number, then add the name of the place of the right-hand figure.

A whole number with a decimal is called a mixed decimal. In reading a mixed decimal, use the word and between the whole number and the decimal.

Much drill in reading and writing decimals is desirable. Bead the following:

.408                 .0050                 32.037                  .000058

.0506               .00401                20.070                  .000506

.0458               .02000                 9.009                  .002600

Express the following in decimal form: 3           5           ^L           ®L           32°            475            _4             4

To  To   Too   Too   looo   Tooo  8To  32ioo

7 tenths                         425 thousandths                8 and 6 tenths

8 hundredths                   62 thousandths              12 and 6 hundredths 32 hundredths                      6 thousandths              15 and 6 thousandths

ADDITION AND SUBTRACTION OF DECIMALS.

Use same method as in whole numbers. Arrange units of the same order in the same column. Keep the decimal points one under another.

Place the decimal point in the answer directly under the decimal points in the example.

EXEECISE 10. Addition:

1.   2.457+3.576+8.01+.4592+82.4070

2.   9.423+732.01+62.+8.4067+4.04863

3.   24.84+8.531+.4004+6.07

4.   14.4278+3.042+2.0046+.8795+3.6745+.297

5.   2.243+5.1462+3.0481+.72546+.04652